Ionic2 RC build problems

ionic serve works fine,
ionic build/emulate ios/android give me a main.js file with only this in it

!function(){"use strict"}();

no errors shown in build log

ionic serve runs the build process in development mode. ionic build runs it in production mode by default.

Can you try and run the following command to see if the issue has anything to do with prod/dev settings:

npm run build --dev

good thought but same behavior

[10:05:03]  ionic-app-scripts 0.0.30
[10:05:03]  build dev started ...
[10:05:03]  clean started ...
[10:05:03]  clean finished in 8 ms
[10:05:03]  copy started ...
[10:05:03]  bundle dev started ...
[10:05:03]  lint started ...
[10:05:03]  copy finished in 196 ms
[10:05:04]  lint finished in 1.14 s
[10:05:14]  bundle dev finished in 11.00 s
[10:05:14]  sass started ...
[10:05:15]  sass finished in 955 ms
[10:05:15]  build dev finished in 11.97 s

and then main.js seems unchanged at

!function(){"use strict"}();